ZIP 66021 falls in Johnson County, Kansas, where we hold 33 septic-related documents. We have not classified septic-versus-sewer status for this county, and we do not have a per-ZIP parcel count -- see the county page for what we hold and where the records are kept.
ZCTA 66021 is not entirely inside one county. Land-area share is from the 2020 Census ZCTA-to-county relationship file.
| County | Land in this ZIP | Documents held | On septic (county) | On sewer (county) |
|---|---|---|---|---|
| Johnson County, Kansas | 64% | 33 | — | — |
| Miami County, Kansas | 26% | 11 | — | — |
| Douglas County, Kansas | 9% | 10 | — | — |
Land-area overlap is from the 2020 Census Bureau ZCTA5-to-county relationship file, not an estimate of ours. Parcel and document counts are rows we hold, not a survey of every property in the ZIP. Last verified 2026-09-01.
We have not measured septic-versus-sewer status for this county yet.
ZIP 66021 spans 3 counties: Johnson County, Kansas, Miami County, Kansas, Douglas County, Kansas.